Repair Shop Manual. Air Heaters. Air Top 2000 Diagnosis. Air Top Type AT 2000 B (Fuel) Type AT 2000 D (Diesel)

Transcription

1 Air Heaters Repair Shop Manual Air Top 000 Diagnosis Air Top 000 Type AT 000 B (Fuel) Type AT 000 D (Diesel) 07/000

2 Air Top 000 List of Contents List of Contents Introduction. Scope and Purpose Use of Air Heaters Meaning of Warnings, Cautions and Notes Additional Documentation to be used Safety Information and Regulations Legal Provisions for Installation General Safety Notes Corrections and Improvements General Description. Combustion and Heating Air Fan Heat Exchanger Burner Insert with Combustion Tube Control Unit / Control Circuit Board Flame Sensor Glow Plug Temperature Limiter Dosing Pump Functional Description 3. Functional Description Air Top 000 without Diagnosis Control Element Switch-On Stabilization Heating Operation Control Operation Control Idle Switch-Off Functions of the Air Heater in ADR Vehicles Switch-off upon Failure Functional Description Air Top 000 Diagnosis Control Element Switch-On Stabilization Heating Operation Control Operation Control Idle Switch-Off Functions of the Air Heater in ADR Vehicles Switch-off upon Failure Technical Data I

3 List of Contents Air Top Troubleshooting 5. General General Failure Symptoms Failure Symptoms during Operation Error Code Output (Air Top 000 Diagnosis) Functional Tests 6. General Adjustments Adjustment of the CO Contents Components Testing Glow Plug Resistance Test Flame Sensor Resistance Test Circuit Diagrams 7. General Servicing 8. General Work on the Air Heater Work on the Vehicle Air Heater Test Run Servicing Visual Inspections and Installation Regulations Heating Air System Fuel Supply Dosing Pump Fuel Filter Combustion Air Supply Exhaust Line Combustion Air Intake and Exhaust Lines Electrical Connections Removal and Installation Air Heater, Removal and Installation Replacement of Control Unit Replacement of Temperature Limiter Installation of new Control Units Replacement of Control Unit Air Top 000 ( Volt) with External Temperature Sensor Replacement of Control Unit Air Top 000 (4 Volt) not ADR Replacement of Control Unit Air Top 000 (4 Volt) ADR First Operation... 8 II

4 Air Top 000 List of Contents 9 Repair 9. General Work on Components after Disassembly Incorporation of Modifications Disassembly and Assembly Removal of Housing Components/Covers Replacement of Control Unit Replacement of Temperature Limiter Replacement of Combustion Air Fan Replacement of Flame Sensor Replacement of Glow Plug Replacement of Burner Insert, Combustion Tube, and Heat Exchanger Packaging/Storage and Shipping 0. General III

5 List of Figures Air Top 000 List of Figures 30 Functional Diagram (Air Top 000 without Diagnosis) General Failure Symptoms Failure Symptoms during Operation Adjustment of CO Contents Terminal Pin Assignment, Air Top 000 Diagnosis Terminal Pin Assignment, Air Top 000 without Diagnosis Circuit Diagram Automatic Control Air Top 000 Diagnosis, V/4V with Control Element Circuit Diagram Automatic Control Air Top 000 Diagnosis, V/4V with Combination Timer Circuit Diagram Automatic Control Air Top 000 Diagnosis, V/4V with Control Element and Standard Timer Circuit Diagram Automatic Control Air Top 000 Diagnosis, 4V ADR Operation with Control Element Circuit Diagram Automatic Control Air Top 000 Diagnosis, 4V ADR Operation with Combination Timer Circuit Diagram Automatic Control Air Top 000 Diagnosis, 4V ADR Operation with Combination Timer and Auxiliary Drives Circuit Diagram Automatic Control Air Top 000 without Diagnosis, V with Control Element Circuit Diagram Automatic Control Air Top 000 without Diagnosis, V with Control Element and Timer Circuit Diagram Automatic Control Air Top 000 without Diagnosis, 4V with Control Element Circuit Diagram Automatic Control Air Top 000 without Diagnosis, 4V with Control Element and Timer Circuit Diagram Automatic Control Air Top 000 without Diagnosis, 4V with Control Element, ADR Circuit Diagram Automatic Control Air Top 000 Diagnosis, 4V ADR Operation with Control Element in Vehicles without Auxiliary Drive Connection Diagram, Air Top 000 Diagnosis with Combination Timer (not ADR!) Fuel Supply Webasto Fuel Tank Tap Fuel Tapping from Plastic Tank (tapping via fuel drain plug) Fuel Tapping from Plastic Tank (tapping via fitting plate) Pipe/Hose Connection Dosing Pump, Installation Position and Attachment Fuel Filter Exhaust Muffler, Direction of Flow Exhaust Pipe Outlet, Installation Position Removal of Fuse Holder Attachment Plate Fuse Holder, Installation Position Control Element Pulling the Plug Example of an Installation Replacement of Control Unit and Temperature Limiter (Air Top 000 without Diagnosis) Replacement of Control Unit and Temperature Limiter (Air Top 000 Diagnosis) Removal of Housing Components/Covers Replacement of Combustion Air Fan (Removal) Replacement of Combustion Air Fan (Disassembly) Disassembly of Heat Exchanger IV

6 Air Top 000 Introduction Introduction. Scope and Purpose This repair shop manual is intended to support familiarized personnel in the repair of air heaters Air Top 000 of the fuel and Diesel type as well as of Air Top 000 Diagnosis with serial no and up... Use of Air Heaters The air heaters Air Top 000 and Air Top 000 Diagnosis are used to heat the cabin defrost the windscreens. They are not cleared for heating a transportation compartment for dangerous goods. The heaters operate independent from the vehicle engine and are connected to the fuel tank and to the electrical system of the vehicle. Their use is possible in vehicles with water- or air-cooled engines.. Meaning of Warnings, Cautions and Notes WARNINGS, CAUTIONS, and S in this manual have the following meaning: WARNING This heading is used to highlight that non-compliance with instructions or procedures may cause injuries or lethal accidents to personnel. CAUTION This heading is used to highlight that non-compliance with instructions or procedures may cause damage to equipment. This heading is used to highlight and draw specific attention to information..3 Additional Documentation to be used This workshop manual contains all information and procedures necessary for the repair of heaters Air Top 000 and Air Top 000 Diagnosis. The use of additional documentation is normally not necessary. Operating instructions/installation instructions and the vehicle specific installation proposal may be used as complementary information as necessary..4 Safety Information and Regulations The general safety regulations for the prevention of accidents and the relevant operating safety instructions have to be observed at all times."general Safety Regulations" beyond the scope of these regulations are detailed in the following.the specific safety regulations applicable to this manual are highlighted in the individual chapters by Warnings, Cautions, and Notes..4. Legal Provisions for Installation Within the scope of the StVZO (Road Licensing Regulations of the Federal Republic of Germany) "Design General Approvals", laid down by the Federal Office for Motor Traffic, exist for the Water Heater Air Top 000 and Air Top 000 Diagnosis with the following official marks of conformity: ~ S 70 (Diesel) ~ S 77 (Fuel) The installation of the heaters is to be performed in accordance with the installation instructions and must be checked in case of a) the vehicle type inspection in accordance with 0StVZO b) the individual inspection in accordance with StVZO or c) the examination in accordance with 9 StVZO performed by an officially authorised expert or examiner for road traffic, a vehicle inspector or a public servant as per section 4 of Annex VIII b to the StVZO. In the event of c) the installation must be certified on the acceptance certificate included in the copy of the "General Operating License" or on a formsheet according to the specimen of an "approval" included in the Traffic rules 994, Page 48 giving details about manufacturer type of vehicle, and vehicle identification number. This validates the "Design General Approval". The acceptance certificate must be kept with the vehicle. The year of first operation must be permanently marked on the identification label by removing the numerals of the years not applicable. The heat exchanger of the air heater remains serviceable for a maximum of 0 years and must then be replaced with an original spare part by the manufacturer or by one of its authorized workshops. The heater must then be provided with a label marked with the sales date and with the words "Original Spare". When replacing the heat exchanger it is mandatory to also replace the overheat protection element (temperature limiter) to avoid possible malfunctions of old temperature limiters in use. 0

7 Introduction Air Top 000 Should exhaust pipes be routed through rooms accommodating persons, these pipes shall also be renewed after 0 years by original spare parts. When removing the heater the gasket below must be renewed. The heaters are cleared for heating the passenger and driver cabins but not for heating compartments intended for the transportation of dangerous goods. The use of the heater in special vehicles (e.g. vehicles for the transportation of dangerous goods ADR) or vehicles not subject to the StZVO (e.g. ships) are ruled by partially regional regulations. For the installation of the AT 000 D in vehicles used for the transportation of dangerous goods, in addition to the StVZO, the requirements in ADR 00 and ADR 003 (Technical Guidelines for the Transportation of Dangerous Goods on Roads) must be met. Heating Air System Heating air intake openings must be arranged so that under normal operating conditions exhaust fumes of the vehicle engine or air heater are not likely to be expected. Extracting combustion air from the vehicle interior is not permissible. Combustion Air Line The combustion air required must be taken from the exterior. Within rooms accommodating persons, the combustion air lines must not have more than four disconnects and a splash-water protected exterior wall feedthrough. The disconnects must be sealed in a way not to exceed a leak rate of 00 l/h at an overpressure of 0.5 mbar. The line including feedthrough, disconnects, material and specific type must be described in the installation instructions. The line must require tools for installation and removal, must be protected against damage, and must be shockproof. Exhaust Line Heaters must be designed to discharge the exhaust to the exterior. Exhaust pipes must be routed so that exhaust fumes are unlikely to penetrate into the vehicle's interior. The function of any parts of the vehicle essential for its operation must not be impaired. Condensate or water penetrated must not be able to accumulate in the exhaust line. Drain holes are permissible; these must drain the fluid to the exterior via lines sealed against the vehicle interior. The exhaust line outlet is to be positioned to the top, to the side, or in case of exhaust venting below the vehicle floor, to the nearest possible location of the vehicle's or cockpit's side or rear end. In compartments accommodating persons, exhaust lines must not have more than one disconnect and must have a splash-water protected feedthrough in the exterior wall/floor. For water, that has penetrated into the exhaust line, the connection of a drain line with a metal-sealing joint is permissible. The drain pipe must be routed sealed through the exterior wall or the vehicle floor. The heat exchanger, the exhaust line connected, as well as the possible drain pipe must be sealed so that with an overpressure of double the overpressure of the exhaust having the maximum permissible exhaust line length at least however at an overpressure of 0.5 bar a total leak rate of 30 l/h is not exceeded. The line including feedthrough, disconnects, material and specific type must be described in the installation instructions. The line must require tools for installation and removal, must be protected against damage, and must be shockproof. Metal lines must be used. These may not heat to more than 0 C should there be the possibility of contact within the room interior. Protective devices against contact may be fitted. Combustion Air Inlet and Exhaust Outlet During installations these ports for combustion air entry and exhaust fume exit must be of such type, that a ball with a diameter of 6 mm cannot be inserted. Electrical lines, switch gear and control gear of the heater must be located in the vehicle so that their proper function cannot be impaired under normal operating conditions. For the routing of fuel lines and the installation of additional fuel tanks 45 and 46 of the StVZO are to be adhered to. The most important regulations are: Fuel lines are to be designed in such a way that they remain unaffected by torsional stresses in the vehicle, engine movement and the like. They must be protected against mechanical damage. Fuel-carrying parts are to be protected against excessive heat and are to be arranged so that any dripping or evaporating fuel can neither accumulate nor be ignited by hot components or electrical equipment. In busses, fuel lines and fuel tanks may be located neither in the passenger area nor in the driver's compartment. In these type of vehicles the fuel tanks must be located such that they do not pose a direct hazard to the exits in the event of a fire. Fuel supply must not be by means of gravity or pressurization of the fuel tank. 0

8 Air Top 000 Introduction.4. General Safety Notes The heater must not be installed in the passenger or driver compartments of busses. Should the heater nevertheless be installed in such a compartment, the installation box must be sealed tight against the vehicle interior. There must be sufficient ventilation of the installation box from the exterior in order not to exceed a maximum temperature of 40 C in the installation box. Excessive temperatures may cause malfunctions. Installation Instructions for Webasto Fuel Tanks for Fuel Supply of Heaters in Vehicles In busses the installation is not permitted in the passengers or driver's compartment. The fuel filler neck must not be located in the passengers or driver's compartment of any type of vehicle. Fuel reservoirs for carburettor fuel must not be located immediately behind the vehicle front fairing. They must be away from the engine to prevent fuel fires in case of accidents. The same applies to towing vehicles with open cockpit. It is mandatory to install the seal between the heater mounting and the vehicle floor to prevent poisonous exhaust fumes from entering the vehicle interior. All fuel line connections must be tight, must show no damage and have to be inspected in regular intervals (at least in the same frequency as vehicle inspections). When detecting damages or leaks the heater must not be operated until repair will have been performed by an authorised Webasto repair shop. Make heater inoperative by removing fuse. The fuel lines (Mecanyl hoses) must not be in direct contact with the exhaust pipe and be provided with a heat insulation as required to prevent fires. Keep air intakes and exit ports for warm and heating air clean and free from foreign objects. Contaminated and clogged air ducts may cause overheating and response of the temperature limiter. After an overheat condition with automatic switch-off check air ducting is free from contamination and remove all objects that might block the airstream or have damage repaired by an authorized Webasto repair shop. Then reset the temperature limiter. Should these corrective actions not cure the problem (overheating occurs again), consult an authorized Webasto repair shop. Never remove the air intake screen upstream of the heater. Do not step on the heater and do not deposit heavy objects on or throw against the heater. Do not throw garments, fabrics or similar material on top of the heater or in front of the heating air intake or exit. The warm air flow of the heater must not be restricted or blocked by easily flammable substances or material like rags, cleaning wool, etc., to prevent fires and smoke. Flammable or explosive material or gasses must be kept away from the vicinity of the heater, the warm air ducting or the heating airflow. The heater must not be cleaned with water, fluids or high pressure cleaners, etc. Do not switch off heater with the battery master switch or the battery emergency off switch to prevent possible long time damage and malfunctions of the heater. The operating condition of the heater least on or off must be clearly visible. Non-compliance with the installation instructions and its procedures will void the warranty by Webasto. The same applies for repairs performed by unskilled personnel or not using original spare parts. This will also invalidate the official marks of conformity and thus the vehicle s permit of operation. Make sure to read the operating instructions before you operate the heater..5 Corrections and Improvements Deficiencies, improvements, or proposals for correction of this workshop manual are to be mailed to: Webasto Thermosysteme GmbH Abt. Technische Dokumentation D-83 Stockdorf Telefon: 0 89 / Telefax: 0 89 / The air jets with adjustable flops must always be open in a way that the airflow through the heater is not blocked. A frequently restricted or blocked airflow may cause long time damage. Should a heater be located in a stowage compartment, it must be ensured that no flammable material is stowed in this compartment and that other material does not restrict the air supply of the heater. Air lines must be securely fastened to the heater and the air jets (e.g. with pipe clamps). 03

9 Introduction Air Top 000 Page free for notes 04

10 Air Top 000 General Description General Description The air heater Air Top 000 and Air Top 000 Diagnosis with serial no and up operating to the evaporator principle basically consists of: A malfunction in air heaters Air Top 000 Diagnosis outputs an error code to the display of the combination or standard timer. When equipped with a control element the operating indicator flashes. In addition a heater checkout may be performed using a personal computer (refer to operating instructions PC air heater diagnosis). combustion and heating air fan heat exchanger burner insert with combustion tube control unit Air Heater Air Top 000 Diagnosis (covers removed) Air Heater Air Top 000 For control and monitoring a control unit/control circuit board flame sensor glow plug temperature limiter temperature sensor. Combustion and Heating Air Fan The combustion and heating air fan delivers the air required for combustion from the combustion air inlet to the burner insert. By means of the fan the heating air is also delivered to the air outlet. are located within the unit. Volt heaters (Air Top 000 without Diagnosis) may be controlled by means of an external temperature sensor. All heaters of air Top 000 Diagnosis may be controlled by means of an external temperature sensor. Fuel supply is provided externally by a fuel dosing pump. Combustion and Heating Air Fan Air Heater Air Top 000 without Diagnosis (covers removed) 0

11 General Description Air Top 000. Heat Exchanger The heat exchanger dissipates the heat provided by combustion to the air delivered by the combustion and heating air fan..4 Control Unit / Control Circuit Board Air Top 000 without Diagnosis The control unit/control circuit board is the central controlling unit for functional sequencing and monitoring of the combustion operation. A temperature sensor located on the side is used for temperature control. Volt heaters may have the temperature sensor replaced against an external temperature sensor. The combustion and heating air fan may be set by means of a potentiometer. Potentiometer Heat Exchanger.3 Burner Insert with Combustion Tube Within the burner insert fuel is distributed in the combustion tube across the burner cross-section. In the combustion tube the combustion of the fuel/air mixture takes place heating up the heat exchanger. Burner Insert Combustion Tube Temperature Sensor Control Unit Air Top 000 without Diagnosis Air Top 000 Diagnosis The control unit/control circuit board is the central controlling unit for functional sequencing and monitoring of the combustion operation. A temperature sensor located on the control unit is used for temperature control. All heaters may have the temperature sensor replaced against an external temperature sensor. The combustion and heating air fan may be set by means of a potentiometer. A malfunction in air heaters Air Top 000 Diagnosis outputs an error code to the display of the combination or standard timer. When equipped with a control element the operating indicator flashes. In addition a heater checkout may be performed using a personal computer (refer to operating instructions PC air heater diagnosis). 0

12 Air Top 000 General Description Potentiometer Temperature Sensor.7 Temperature Limiter The temperature limiter protects the air heater against excessive operating temperatures. Overheat protection is activated at temperature higher than 50 C to interrupt the electrical circuit of the dosing pump and switch off the heater with run-down operation.after cooling down the electrical circuit is restored. The air heater may be switched on again (see 3.9). Control Unit Air Top 000 Diagnosis Temperature Limiter.5 Flame Sensor The flame sensor is a low-ohm PTC resistor changing its resistance dependent on its heating by the flame. The signals are routed to the control unit for processing. The flame sensor monitors the flame operating condition over the complete duration of heater operation..8 Dosing Pump The dosing pump is a combined supply, dosing and shut-off system for the fuel supply of the heater out of the vehicle's fuel tank. Flame Sensor Dosing Pump DP for Fuel and Diesel operated Heaters.6 Glow Plug The glow plug ignites the fuel/air mixture at the start of the air heater operation. The glow plug is acting as an electrical resistor and is located in the burner insert opposed to the flame side. Dosing Pump DP 30 for Diesel operated Heaters Glow Plug 03

13 General Description Air Top 000 Page free for notes 04

14 Air Top Functional Description 3 Functional Description 3. Functional Description Air Top 000 without Diagnosis (Fig. 30) 3.. Control Element The control element is used to switch the air heater on and off, set the desired room temperature (air intake temperature between 0 C and 45 C), and to unlock a failure interrupt condition. The green LED indication is used to indicate the operating condition (LED permanently on) and an overheat condition (LED flashes). After application of power upon switch-on of the battery switch and selecting the control element "ON", the control unit enters the "error lockout" condition. Prior to a re-activation the control element has to be placed to "OFF". 3.. Switch-On The control element is set to the desired room temperature. When switching the air heater on, the operating indicator is illuminated and the glow plug is activated (cycled). The motor of the combustion and heating air fan starts high-speed operation for second (break-away moment) and is then under slow-down control. Should the temperature of the intake air be above the selected, rated temperature, only the motor of the combustion and heating air fan will operate (control idle). Start operation will be initiated with a heating air temperature below the rated temperature. After approx. 0 seconds (for fuel operated heaters after approx. 5 seconds) the fuel dosing pump is activated. After another 5 seconds the speed of the combustion and heating air fan is continuously increased to a higher rate and combustion begins. As soon as a flame is detected, combustion will be stabilized (see 3..3). Should no normal combustion be achieved within 0 seconds (for fuel operated heaters after approx. 5 seconds), the speed of the combustion and heating air fan is increased for approx. 30 sec and there will be an automatic repeat start with the glow plug activated and fuel dosing pump deactivated (no fuel supply) Stabilization Diesel Operated Heaters With the glow plug activated the operating speed of the combustion and heating air fan is increased. After another 0 seconds the speed of the combustion and heating air fan is continuously increased within 7 seconds to full load for full heat. A flame-out during the speed rise control period causes a repeat start. Fuel Operated Heaters With the glow plug activated the operating speed of the combustion and heating air fan is continuously increased within 4 seconds to full load for full heat. A flame-out during the speed rise control period causes a repeat start Heating Operation During operation the combustion exhaust gasses flow through the heat exchanger charging its walls with combustion heat, which in turn is taken up by the heating air delivered by the heating air fan to be routed to the vehicle interior. The temperature of the heating air sucked in is measured by means of a temperature sensor fitted to the air intake side of the air heater or in case of Volt heaters also by means of an externally located temperature sensor. A temperature below the one set with the control element increases the heater performance up to maximum heat. In order to extend the burner idle period of Diesel operated heaters during permanent operation with a heating performance in excess of. kw, the fuel dosing pump delivery rate is reduced every 30 minutes for 0 seconds. A heating performance less than. kw causes the fuel delivery to the dosing pump to be interrupted every 30 minutes for 4 seconds. For both types of heaters (fuel and Diesel) heating operation is shortly interrupted every 9 hours like in control idle. After reaching the temperature set with the control element, heating performance is controlled to decrease. The speed of the combustion and heating air fan slows down and the fuel delivery rate to the pump is reduced. When exceeding the air intake temperature set with the control element during minimum heating performance, the dosing pump is deactivated after 5 seconds and combustion terminates. The control unit/air heater reacts to new settings of the control element with a time delay. Should the no-combustion-condition persist, after another 80 seconds (for fuel operated heaters after approx. 85 seconds) there will be a switch-off by error lockout (see 3..9) with a run-down of the combustion and heating air fan lasting 0 seconds at /3 of its max. speed. 30

15 3 Functional Description Air Top Control Operation During control operation fan speed and dosing pump rate of delivery are subject to heating performance. The glow plug is deactivated Control Idle In case the air intake temperature set with the control element is exceeded and the minimum heating performance had been achieved for longer than 5 seconds, the fuel supply is cut off to terminate combustion. The motor of the combustion and heating air fan continues operation for another 55 seconds at /3 of maximum speed to cool down the air heater (run-down). In control idle the combustion and heating air fan runs at minimum speed. The operation indication remains lit. After reaching the air intake temperature set with the control element a new start procedure is launched (without break-away) Switch-Off Switching the heater off extinguishes the operation indication of the control element. If no fuel has been delivered (within 0 seconds for Diesel operated heaters or within 5 seconds for fuel operated heaters after switch-on) or if the air heater is in control idle, the air heater is deactivated immediately without run-down. If fuel supply has commenced it will be immediately stopped at switch-off. The fan speed decreases within 35 seconds to /3 of maximum. Subsequently or if the flame sensor detects "no flame" the fan speed is increased to maximum for 60 seconds and run-down is initiated to last 0 seconds. Run-down is automatically halted. Re-activation of the heater during run-down is permitted. Run-down will be completed first with a subsequent re-start Functions of the Air Heater in ADR Vehicles Applicable only for Air Top 000 D Air Heaters installed in vehicles for the transportation of dangerous goods (ADR). The short run-down time depends on the operational condition at which ADR switch-off occurs. A 40 second run-down with maximum speed is initiated (ADR switch-off) when: air heater is still in the start phase; stabilization not yet achieved air heater is in normal run-down air heater is in control idle. A 0 second run-down is switched on in normal combustion operation with the fuel delivery immediately halted maintaining the fan speed for 5 seconds. Then the speed is increased for 30 seconds within another 5 seconds. For all heaters after July 995 the short run-down out of all operating conditions is a max. of 0 seconds. After an ADR switch-off the control unit is in the "error lockout" condition. Prior to resuming operation the control element has to be set to "OFF" Switch-off upon Failure The control unit recognises failures of individual air heater components and malfunctions in the start sequence and in normal operation. The air heater is deactivated and enters the error lockout mode under the following conditions: flame sensor resistance out of tolerance temperature sensor resistance out of tolerance glow plug/glow plug trigger defective fan speed too low, short circuit or open circuit error in dosing pump electrical circuit or of overheat protection (in start phase only) low voltage below 0 Volt and in excess of 0 seconds for Volt heaters low voltage below 0 Volt and in excess of 0 seconds for 4 Volt heaters control unit defective In case of overheating there will be no fuel supply. A run-down like after manual switch-off will be performed. After run-down the control unit is in the error lockout mode. Overheating is indicated by the operation indication flashing. For error unlock the air heater has to be switched off momentarily to be switched on again. If the heater is deactivated using the control element, un-down will not change. A short run-down (max. 40 seconds) is automatically activated if: the vehicle engine is turned off a conveyor facility is put into operation. 30

16 Air Top Functional Description On A B C 0 D 00% 90% 60% 30% 0 E.3 Hz.0 Hz 0.8 Hz 0.6 Hz 0 F typical seconds (0) (60) (0) Fig. 30 Functional Diagram (Air Top 000 without Diagnosis) Start Control Operation 3 Rated Value reached 4 Rated Value exceeded (e.g. due to reduced heat consumption) 5 Run-down 6 Control Idle A = Control Element B = Temperature Sensor C = Glow Plug D = Combustion and Heating Air Fan E = Dosing Pump F = Flame Sensor 7 Start 8 Control Operation (increased heat consumption) 9 Switch-off 0 Run-down 303

17 3 Functional Description Air Top Functional Description Air Top 000 Diagnosis 3.. Control Element The control element is used to switch the air heater on and off, set the desired room temperature (air intake temperature between 0 C and 45 C), and to unlock a failure interrupt condition. The green LED indication is used to indicate the operating condition (LED permanently on) and an overheat condition (LED flashes). ADR Operation: After application of power upon switch-on of the battery switch and selecting the control element "ON", the control unit enters the "error lockout" condition. Prior to a re-activation the control element has to be placed to "OFF". 3.. Switch-On The control element is set to the desired room temperature. When switching the air heater on, the operating indicator is illuminated and the glow plug is activated (cycled). The motor of the combustion and heating air fan starts high-speed operation for second (break-away moment) and is then under slow-down control to approx. 30% (Diesel) or 50% (fuel) of full speed. Should the temperature of the intake air be above the selected, rated temperature, only the motor of the combustion and heating air fan will operate (control idle). Start operation will be initiated with a heating air temperature below the rated temperature. The flame sensor function is checked. If the flame sensor at this time already signals "flame", there will be a 0 second run-down and an error lockout of the control unit. A malfunction of any other component monitored causes an error lockout without run-down. After approx. 0 seconds (for fuel operated heaters after approx. 5 seconds) the fuel dosing pump is activated. After another 5 seconds the speed of the combustion and heating air fan is continuously increased to a higher rate and combustion begins. As soon as a flame is detected, combustion will be stabilized (see 3..3). Should no normal combustion be achieved within 0 seconds (for fuel operated heaters after approx. 5 seconds), the speed of the combustion and heating air fan is increased for approx. 30 sec and there will be an automatic repeat start with the glow plug activated and fuel dosing pump deactivated (no fuel supply). Should no proper combustion develop within 0 seconds (for fuel-operated within 5 seconds) the combustion and heating air fan speed is increased to full load for approx. 30 seconds (5 seconds for fuel-operated heaters) with the glow plug on and the dosing pump off (no fuel delivery) with a subsequent automatic restart. Should the no-combustion-condition persist, after another 80 seconds (for fuel operated heaters after approx. 85 seconds) there will be a switch-off by error lockout (see 3..9) with a run-down of the combustion and heating air fan lasting 0 seconds at /3 of its max. speed.. Start (automatic restart) Fan speed is again reduced to approx. 30% (for fuel operated heaters to approx. 50%) and fuel is delivered. During the next 0 seconds fan speed is increased to approx. 60% (for fuel-operated heaters to approx. 75%) of full speed. As soon as a flame is detected within the next 55 seconds, combustion will be stabilized. Should there be no flame condition after a total fuel delivery period of 80 seconds, fuel delivery will be stopped and the glow plug deactivated. The combustion air fan continues full load operation for another 0 seconds (run-down) and the heater enters the error lockout condition Stabilization Diesel Operated Heaters With the glow plug activated the operating speed of the combustion and heating air fan is increased. After another 0 seconds the speed of the combustion and heating air fan is continuously increased within 7 seconds to full load for full heat. This operating condition is omitted if the set temperature (control idle) has already been achieved once. The glow plug is deactivated and heating operation commences. A flame-out during speed up control causes a restart, 5 restarts an error lockout of the heater. Fuel Operated Heaters With the glow plug activated the operating speed of the combustion and heating air fan is continuously increased within 4 seconds to full load for full heat. This operating condition will be omitted if the start occurs after a control idle period. The glow plug is deactivated and heating operation commences. A flame-out during speed up control causes a restart, 5 restarts an error lockout of the heater. 304

18 Air Top Functional Description 3..4 Heating Operation During operation the combustion exhaust gasses flow through the heat exchanger charging its walls with combustion heat, which in turn is taken up by the heating air delivered by the heating air fan to be routed to the vehicle interior. The temperature of the heating air sucked in is measured by means of a temperature sensor fitted to the air intake side of the air heater or by means of an externally located temperature sensor. A temperature below the one set with the control element increases the heater performance up to maximum heat. In order to extend the burner idle period of Diesel operated heaters during permanent operation with a heating performance in excess of. kw, the fuel dosing pump delivery rate is reduced every 5 minutes for 0 seconds. A heating performance less than. kw causes the fuel delivery to the dosing pump to be interrupted every 30 minutes for 4 seconds. Additionally heating operation is briefly suspended every 9 hours like in control idle. For Diesel-operated heaters this is only applicable, if at this time heating performance is less than. kw Control Operation During control operation fan speed and dosing pump rate of delivery are subject to heating performance. The glow plug is deactivated Control Idle After reaching the temperature set with the control element, heating performance is controlled to decrease. The speed of the combustion and heating air fan slows down and the fuel delivery rate to the dosing pump is reduced. When exceeding the air intake temperature set with the control element during minimum heating performance, the dosing pump is deactivated after 5 seconds and combustion terminates. Fan speed remains constant for 35 seconds and is then increased to approx. 60% of full speed for cooling the heater down. the fan then continues to operate at approx. 30% of full speed until temperature is below the temperature set with the control element. If temperature falls below the one set with the control element, the heater will restart (without break away). New settings on the control element are executed by the control unit/heater with a time delay Switch-Off Switching the heater off extinguishes the operation indication of the control element. If no fuel has been delivered or if the air heater is in control idle, the air heater is deactivated immediately without run-down. If fuel supply has commenced it will be immediately stopped at switch-off. Fan speed remains constant and then decreases within 30 seconds to approx. 60% of full speed. After this or with the flame sensor detecting "no flame", fan speed rises to maximum speed for 60 seconds and run down for 0 seconds is initiated. Run-down is at approx. 60% of full speed and is deactivated automatically. Re-activation of the heater during run-down is permitted. Run-down will be completed first with a subsequent re-start Functions of the Air Heater in ADR Vehicles Applicable only for Air Top 000 D Air Heaters installed in vehicles for the transportation of dangerous goods (ADR). If the heater is deactivated using the control element, run-down will not change. A short run-down (max. 0 seconds) is automatically activated if: the vehicle engine is turned off a conveyor facility is put into operation The short run-down time depends on the operational condition at which ADR switch-off occurs. A 5 second run-down with maximum speed is initiated (TRS switch-off) when: air heater is still in the start phase; stabilization not yet achieved air heater is in normal run-down air heater is in control idle. A 0 second run-down is switched on in normal combustion operation and in stabilization with the fuel delivery immediately halted maintaining the fan speed for 5 seconds. Then the speed is increased to maximum for 5 seconds within for a run-down. After an ADR switch-off the control unit is in the "error lockout" condition. Prior to resuming operation the control element has to be set to "OFF". 305

19 3 Functional Description Air Top Switch-off upon Failure The control unit recognises failures of individual air heater components and malfunctions in the start sequence and in normal operation. The air heater is deactivated and enters the error lockout mode under the following conditions: flame sensor open or short circuit temperature sensor open or short circuit glow plug open or short circuit fan motor open or short circuit or fan speed wrong dosing pump open or short circuit overheating low voltage below 0 Volt or high voltage above 5 Volt in excess of 0 seconds for Volt heaters low voltage below 0 Volt or high voltage above 30 Volt in excess of 0 seconds for 4 Volt heaters A switch-off like in "switch-off" will be performed. In case of overheating there will be no fuel supply. After run-down the control unit is in the error lockout mode. The operation indication outputs a flash code. For error unlock the air heater has to be switched off momentarily (at least seconds) to be switched on again. 306

20 Air Top Technical Data 4 Technical Data As long as no threshold values are given, the following technical data are understood to include tolerances of ±0% usual for heaters at an ambient temperature of +0 C and at nominal voltage and conditions. Electrical Components: Control unit, combustion air fan, dosing pump, timer*, glow plug and control element are for or 4 Volts operation. The components temperature limiter and flame detector are independent of voltage. Propellant for Air Top 000 B (Fuel): The proper fuel is the fuel specified by the vehicle manufacturer. Propellant for Air Top 000 D (Diesel/Fuel Oil EL): The proper Diesel fuel is the one specified by the vehicle manufacturer. Also fuel oil of class EL not heating oil L can be used as long as it meets the standard German quality specified in DIN A persistent influence by additives is not known. When tapping fuel from the vehicle fuel tank observe the manufacturer s fuel additive specifications. When switching to low temperature propellants the heater must be operated for at least 5 minutes to prime the fuel system with the new type of fuel. * not for ADR Air Heater Operation AT 000 B AT 000 D Mark of conformity ~ S 77 ~ S 70 Heater type Air heater with evaporator burner Heat flow Control range..0 kw kw Type of fuel Fuel Diesel/Fuel oil (EL) Fuel consumption Control range kg/h ( l/h) kg/h ( l/h) Nominal voltage Volt Volt 4 Volt Operation voltage Volt Volt Volt Rated power consumption Control range 9... W Permitted ambient temp.: Heater operation storage Dosing pump operation storage Control element operation storage Permitted combustion air intake temperature Setting range for indoor temperature Volume flow of heating air against 0.5 mbar CO in exhaust (perm. functional range) Dimensions air heater Weight, heater Control range C C C C C C C C Max. 70 m 3 /h Max Length 3 ± mm Width 30 ± mm Heigh ± mm.6 kg 40

21 4 Technical Data Air Top 000 Page free for notes 40

22 Air Top Troubleshooting 5 Troubleshooting 5. General This section describes troubleshooting procedures for the Air Heater Air Top 000 and Air Top 000 Diagnosis. A malfunction in air heaters Air Top 000 Diagnosis outputs an error code to the display of the combination or standard timer. When equipped with a control element the operating indicator flashes. In addition a heater checkout may be performed using a personal computer (refer to operating instructions PC air heater diagnosis). CAUTION Troubleshooting requires profound knowledge about structure and theory of operation of heater components and may only be performed by skilled personnel. In cases of doubt refer to Sections or 3 for functional interrelations. Only for ADR operation After an ADR switch-off or power application by vehicle main power switch operation and the control element to "ON", the control unit will be in "error lockout". Prior to reactivation the control element must be set to "OFF" or the instant heat switch on the combination or standard timer be operated. CAUTION Troubleshooting is normally limited to the isolation of defective components. The following causes for trouble are not considered and should always be checked for to exclude them as cause for trouble: corrosion on connector loose contact on connector wrong crimping on connector corrosion on electrical wiring and fuses corrosion on battery terminals If individual components are checked, the control unit electrical connections must be disconnected. After any correction of a failure a functional test has to be performed in the vehicle. 5. General Failure Symptoms The following table (Fig. 50) lists the possible failure symptoms. Failure Symptom Probable Cause Remedy Air heater switches off automatically Heater expels black fumes No combustion after start or repeat start Flame extinguishes during operation Heater overheats Operation indication flashes Vehicle electrical system voltage too low Combustion air and/or exhaust ducting blocked Switch off heater momentarily and switch on once again Switch off heater momentarily and switch on once again Check heat air ducting for obstuctions, allow heater to cool down, switch off heater momentarily and switch on once again Charge battery Switch off heater momentarily and switch on once again Check combustion and exhaust ducting for obstructions Fig. 50 General Failure Symptoms 50

23 5 Troubleshooting Air Top Failure Symptoms during Operation The following table (Fig. 50) lists the possible failure symptoms as they might occur during the functional sequence of operation. In case of malfunction the failure is to be isolated and removed using this table. It is important to accurately identify the failure symptom. Should the failure symptom not be contained in this table or the trouble not be detected under the specific failure symptom listed, in emergencies assistance by our service technicians may be requested (Tel / 93 78). Overheating and dosing pump failure are always indicated additionally after run-down by the flashing LED of the control element. In all cases of trouble also a defective control unit may be the cause should all other components turn out to be serviceable. Failure Symptom Shows after...s Possible Causes No start and no illumination of LED on control element No start but LED illuminates Very low speed with no start Motor operates momentarily and then stops Stoppage without run-down Run-down after Run-down after Run-down after and dosing pump does not cycle Run-down after Run-down after Run-down Stoppage without run-down Interruption of dosing pump cycling and max. speed for 30 s with subsequent re-start immediately immediately immediately to 0 30 during combustion operation during combustion operation during combustion operation Wrong cabling, defective fuse Fan or control unit defective or fan blocked Control idle operation: wrong manual control (selected temperature is below air intake temperature) or wrong integration (excessive air intake temperature) Glow plug or flame sensor short or open circuit or control unit defective Fan motor obstructed, binding Flame detection erroneous Voltage to control unit too low Cabling to dosing pump, pump itself or overheat protection defective Intermittent disconnect of connection to dosing pump or to overheat protection No flame: wrong fuel supply quantity, defective or slow fan, coked burner (in particular pilot flame outlet bore), combustion air/exhaust ducting obstructed or heat exchanger coked, dosing pump seized Overheating or voltage too low or component error (flame sensor, glow plug, overheat sensor, dosing pump, burner) or no fuel supply or obstructed combustion air/exhaust ducting Fan motor failure or seizure Flame-out by gas bubbles in fuel delivery or strong wind against exhaust outlet or defective no-flame detection Fig. 50 Failure Symptoms during Operation 50

24 Air Top Troubleshooting 5.4 Error Code Output (Air Top 000 Diagnosis) When equipped with a combination or standard timer a malfunction will cause an error code output to the display of the timer for indication. When equipped with a control element the error code output is indicated by flashing of the operating indicator/ error code indication. The number of flash pulses corresponds to the number indicated in the table below. After a quick pulse train there will always be an error code output. Error code output on display of combination or standard timer F 0 No start (after attempts) F 0 Flame out (at least > 5) F 03 Voltage too low or too high F 04 Premature flame detection F 05 Flame sensor open or short circuit F 06 Temperature sensor open or short circuit F 07 Dosing pump open or short circuit F 08 Fan motor open or short circuit or wrong speed F 09 Glow plug open or short circuit F 0 Overheating 503

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26 Air Top Functional Tests 6 Functional Tests 6. General This section describes the on-vehicle and off-vehicle testing of the air heater to check its proper operation. WARNING The air heater shall not be operated in enclosed areas like garages or workshops not provided with exhaust venting facilities. 6. Adjustments 6.. Adjustment of the CO Contents 6... General The CO contents of the exhaust is adjusted with the potentiometer on the control circuit board.the air heater is preset by the manufacturer with respect to the combustion and heating air fan fitted. After adjustment by the manufacturer the potentiometer is in center position (Fig. 60). After an inadvertent loss of this position it is sufficient to restore its original position. CAUTION Set potentiometer slowly; observe end positions. Adjustment may be performed at any electrical system voltage. Clockwise rotation increases the fan speed and decreases the CO contents. Counterclockwise rotation decreases the fan speed and increases the CO contents. If the setting range is not sufficient (e.g. after replacement of the combustion and heating air fan) the manufacturer's setting may be cancelled according to the procedure described in the following New Basic Setting CAUTION The manufacturer's setting cannot be restored.. Withdraw cover from upper shell according to Switch on air heater. 3. Rotate potentiometer two times and with no interrupt through its complete setting range (e.g. max. - min.- max.). 4. Adjust desired CO contents (Fig. 60). 5. Switch off air heater. 6. Plug on cover and secure. The manufacturer setting may be corrected by rotating the potentiometer. A suitable tool like a small screw driver (.5 mm tip) is to be used. CO + CO + Air Top 000 Diagnosis Air Top 000 without Diagnosis Fig. 60 Adjustment of CO Contents 60